Scales, barcodes and labels — Paloma POS 2

This article covers Paloma POS 2 — the new touch-screen POS app in the Paloma line. It explains working with weighed goods: scanning barcodes with a handheld scanner, using a scale at the till, weight barcodes and PLU, and packing goods to print labels (weighed and piece, in different sizes and designs). If you're not sure this is your app, start with «How to tell you have Paloma POS 2». Adding items to an order is covered in «Quick sale».

Overview

• A barcode scanner (a handheld HID scanner) acts like a keyboard: aim it at a barcode and the item is added to the order at once. No setup needed.
• A weighed item is sold by weight (per kilogram). In the menu editor it has a PLU (code), so scales and labels recognise it by that code.
• A till scale connects to the device over USB / COM or over the network (TCP). When you weigh, the app shows the weight and lets you drop it into the line with «Use weight».
• A weight barcode is an ordinary barcode with the item code and weight (in grams) embedded inside it. The app recognises it and fills in both the item and the weight.
• Packing is a separate screen: weigh an item and print a label for it with a barcode, price and, optionally, dates. Open it with the «Packing» tile on the home screen.

Scale and barcode settings live under «Scales» (weights · barcodes · labels). Marked goods (track-and-trace codes) are scanned differently — that is a separate topic and isn't covered here.

Step 1. Scan a barcode in the order

A handheld scanner connected to the tablet or POS terminal acts like a keyboard: it «types» the barcode digits and presses Enter at the end.

1. Open an order (quick or table).
2. Aim the scanner at the item barcode and press the scanner button.
3. If an item with that barcode exists in the menu, it's added to the cart as one line — just like tapping a tile.

You don't need to focus a field first — the app captures scanner input on the order screen automatically.

Step 2. Weight barcode (code + weight inside)

Label-printing scales (for example, when pre-packing fruit or meat) print a barcode with the item code and weight encoded inside. The app recognises it by its prefix:

• The first two digits are the prefix: they mark a «weight» barcode versus a «piece» barcode. By default the weight prefix is 22 and the piece prefix is 21.
• Then comes the item code (PLU) and the weight in grams.

When you scan a weight barcode, the app finds the item by its code and fills in the weight — you don't enter the quantity by hand.

If your scales print barcodes with a different prefix or with an inner check digit, open «Scales» → «Weighing-scale barcodes» and set the weight prefix, the piece prefix and, if needed, the inner check digit. A prefix is exactly two digits (for example, 22).

Step 3. Connect a scale to the till

A benchtop scale connects to the till so you can weigh right on the screen.

1. Open «Scales» → «Scale settings» and turn on «Enable scale».
2. Pick the «Model» — «MASSA-K» or «Shtrikh-Slim».
3. Choose how it connects: «USB / COM» or «Network (TCP)».
   • For USB / COM set the «COM port / device path» and «Baud rate».
   • For the network set the «Host» and «Port».
4. You can tap «Auto-detect» — the app searches for a scale and offers to pick the device it found.
5. Save.

Once connected, a scale strip appears on the weigh screen: «{weight} kg», the status «Stable» or «Stabilising…», and the buttons «Tare», «Zero», «Use weight». Tap «Use weight» to drop the reading into the line quantity. While it's connecting, the strip shows «Connecting to scale…».

Step 4. Weigh and print a label (Packing)

The «Packing» screen lets you weigh an item and print a barcode label for it — the same one that's later scanned at the till (see Step 2).

1. On the home screen tap the «Packing» tile.
2. Find the item in the list or via search and select it. The list holds only weighed items — if there are none, the app shows «No weighed items».
3. Enter the weight in the «Weight» field or, if a scale is connected, tap «Use weight».
4. If needed, pick the «Price type» (defaults to the main price), the «Design» and the «Size» of the label.
5. Set the «Copies», and for date designs the «Best before».
6. Check the preview and the barcode, then tap «Print label». The app shows «Label sent to printer».

The label mode switches between «Weighed» and «Piece». Piece items need no weight — a quantity is printed.

Step 5. Pick a label size and design

Size. The «Size» row shows three popular sizes — 58 × 40, 58 × 30, 40 × 25 mm — plus a «More sizes» dropdown with the rest. Choose the size that matches the labels on your roll.

Design. In the «Design» row pick a layout — for weighed labels, options such as «With dates» and «With logo»; for piece labels, options such as «With dates» and «With logo & dates». The date designs print the packed and best-before rows; a manufacturing-date design prints only the manufacturing date. You can fine-tune each format's layout in «Label templates».

Weighed item and PLU

For an item to be weighable and printable, it must be a weighed item with a PLU. This is set in the menu editor (in the dashboard or in the POS item editor): a weighed item gains a «PLU» field, pre-filled with a suggested free code. That code is how the weight barcode, the scales and the labels recognise the item.

Label scales (they print labels themselves)

Separately, there are «Label scales» — scales that print labels on their own without the till (models Rongta RLS, Massa-K (VPM), Mertech M-ER). They need the item list with prices pushed to them:

1. Open «Label scale» and tap «Add scale», or «Discover» to find a scale on the network.
2. Set the «Host (IP)», «Port», and if needed the price multiplier and barcode prefix.
3. Tap «Sync now» — the items are sent to the scale. The app reports how many items were accepted.

Common problems

• «Item not found: [code]» — the barcode isn't tied to any menu item, the item is on the stop list, or it hasn't synced yet. Check the item's barcode in the menu editor; if it was just created in the dashboard, go back to the home screen and reopen the order so the catalog re-reads.
• «Connecting to scale…» never turns into a weight — the scale isn't responding. Check the cable/power and the address: for USB / COM the «COM port / device path» and baud rate, for the network the «Host» and «Port».
• «Scale not found» on auto-detect — the app didn't find a scale. Enter the connection settings by hand and save.
• «No weighed items» on Packing — no item is marked as weighed with a PLU. The app hints: add weighed items with a PLU in the menu editor so you can print labels.
• «Enter a weight to print» — no weight is set. Enter it by hand or tap «Use weight» on a connected scale.
• «No scale found on the network» when discovering label scales — make sure the scale is on and on the same network as the till, or add it by hand by address.
• «Sync skipped (disabled or no host)» — a label scale has sync off or no address. Turn the scale on and set its «Host (IP)».
• A label won't print — make sure the label printer is set up and present. Printer setup is covered in a separate article about printers.

FAQ

Do I need to set up the barcode scanner?

Usually no. A handheld scanner acts like a keyboard: aim it at a barcode in an open order and the item is added. Settings are only needed for weight barcodes (the prefixes) under «Weighing-scale barcodes».

How does a weight barcode differ from an ordinary one?

An ordinary barcode encodes only the item code. A weight barcode also embeds the weight in grams, and its first two digits (the prefix) mark it as a weight code. The app fills in both the item and the weight.

How is «Packing» different from «Label scales»?

«Packing» is when you weigh an item at the till and print a label through a label printer. «Label scales» are standalone scales that print labels themselves; the till only pushes them the item list via «Sync now».

How do I make an item weighed?

In the menu editor mark the item as weighed — it gains a «PLU» field with a suggested free code. After that the item appears in the «Packing» list and can be weighed and labelled.

Can I print dates on a label?

Yes. Pick a «With dates» design (or, for piece items, «With logo & dates») and set the «Best before» — the label prints the packed and best-before rows. A manufacturing-date design prints the manufacturing date only.

What if the scale shows «Stabilising…»?

Wait for «Stable» — the weight will stop drifting. If needed, zero the scale with «Zero» or set a tare with «Tare», then tap «Use weight».